Single ply roof guarantees typically cover 15-20 years, but these roofs can...

https://melissafreshmaid.com/tpo-vs-pvc-lifespan-what-matters-more-than-the-material/

Single ply roof guarantees typically cover 15-20 years, but these roofs can often last 25-40 years with the right care. Guarantees mainly cover material faults, not wear and tear or maintenance issues